Maryland Code, Health-General § 24-906

(a)(1) Each Program participant shall be issued a unique identification card with a unique identification number.

(2) The unique identification number may not be cross-indexed to any personal identifying data on the participant.

(1) Confidential;

(2) Not open to public inspection or disclosure; and

(3) Not discoverable in any criminal or civil proceeding.

(c)(1) Notwithstanding the provisions of subsection (b) of this section, on the written consent of a Program participant, information obtained by a Program that identifies the Program participant may be released or disclosed to an individual or agency for purposes of linking to services under § 24-903(a)(6) of this subtitle.

(2) In addition to the provisions of paragraph (1) of this subsection, if a Program participant raises the issue of participation in a Program either as a subject matter or legal defense in an administrative, civil, or criminal proceeding, the Program participant waives the confidentiality as to identity provided under subsection (b) of this section.

(3) Substance-related treatment records requested or provided under this section are subject to any additional limitations on disclosure or re-disclosure of a medical record developed in connection with the provision of substance-related treatment services under State law or 42 U.S.C. § 290dd-2 and 42 C.F.R. Part 2.